Ok, so, here is a little bit of ESO confusion I found regarding why Aedra don't exhibit the same level of presence and direct communication as the Daedra. So, the impression I got about the creation of Mundus and Nirn is that the Aedra we worship now as the eight divines sacrificed so much of their power to create and stabilize Nirn, that they eventually lost the ability to directly influence and manipulate Nirn. Unlike the Daedra who can frequently communicate with their followers and quite often display real, tangible power, the Aedra seem to be so bound up by Mundus that they don't have the power to directly communicate with the world anymore. Perhaps through prayer or meditation on the shrines some priests might receive visions or messages from the Divines, but apart from Akatosh's involvement and the Amulet of Kings, I can't really recall other scenarios where the Aedra have actually influenced Mundus after its creation. This interpretation, I think, goes along with the theme of sacrifice and Lorkhan's treachery - one of the most dire results coming from the decision to create Mundus was that many lesser Aedra simply perished or became the earthbones, while the greater Aedra invested so much of themselves that their powers greatly diminished - they became constants and laws, rather than direct sentient forces influencing Nirn, unlike the Daedra. When we add in that the Aedra can actually be killed as part of the covenant with Nirn, the theme of sacrifice and pain for the Aedra is much clearer, and also goes in to explain why the Altmer hate Lorkhan with such intensity.

Ok, but in ESO this new piece of lore came up - http://esohead.com/books/877-daedra-worship-the-chimer, this book looks like is aimed at new players in particular, as in the beginning it goes on to explain how the Aedra and Daedra are different. Apart from the blatant disregard for the Aldmeri language ("Aedra" means "our ancestors," and not "Gods, Divines"), the author just simply states that basically the Aedra became disinterested in Nirn and withdrew from the world, being described as some aloof deities who do not wish to pay attention to what's going on in Mundus. Ok, so we clearly see a very big shift, at least for me, because this very, very clearly contradicts what I have been learning in TSE so far about the Aedra. Sadly, this "rendition" of the Aedra is quite boring and to me doesn't make any sense, no sacrifice, no restraint and no inability to actually show their divine powers. Just "aloof'" - how unoriginal.

Ok, so what do you guys think? Am I right for picking up on this? Does this make sense?

Well noticed, I hadn't spotted that difference before. You're quite right to note that there are differences in the way the Aedra are seen. However what you seem to see as the right one, incorporating themes of sacrifice or loss, is predominantly the Elven perspective (and the Cyrodiilic one, excepting that the gods are willfully deteriorating rather than bound by Lorkhan in that version). Nords for instance have substantially more violent and active gods in their myths (still, for the most part, roughly the same beings at heart as the Merrish gods) either as a result of Skyrim's inhospitable climate affecting the way they see gods and nature, or the influence of the Dawn and other kalpas on their stories.

I admit that the reduction of the creation myth shown in this text is a fairly new perspective; I think it boils down to a combination of the author's bias (Phrastus is primarily portrayed in his works as doubting most things numinous, or taking the most safe, uncontroversial angle) and the version of the monomyth told to second-era Bretons. If it seems to have less grace and drama than http://www.imperial-library.info/content/monomyth then that could be deliberate; see ESO books by Cinnabar of Taneth for a number of criticisms of Phrastus of Elinhir's angle. (also, I don't think he's defining the term "Aedra" as "the Gods, the Divines" but rather saying these are cultural variations on the same concept).

But at the same time, you could consider what it means for the gods to become aloof. If the people are ceasing to believe that the Aedra gave their divinity to Nirn itself, but rather left it, this could be a sign of a period of secularism and doubt in the usual powers. Fitting for the Interregnum. Also, there is some precedent for the idea of aloof gods: I vaguely recall a phrase (maybe it came up in Memospore some time?) about the gods leaving the Mundus to "cool"; the transition from instability of Dawn Era through the myth of the Merethic into more concrete history has a number of explanations, all of which play a part in Convention: the death of Lorkhan, the solidification of the Earthbones, some action on the part of Y'ffre or another deity; the absence of the gods themselves is just a further variation on the idea of the Mundus becoming "normal" and inhabitable. It explains to some degree how gods are sometimes active on the Mundus without requiring tricky concepts like "decaying, but not dead" or "dead, but not inactive".

So I'd say that you can regard this as another myth, and if you feel it's less interesting than extant ones, Phrastus of Elinhir will bear your doubt. Also, it's nothing new for introductory Tamrielic divinity texts to have gaping errors - http://uesp.net/wiki/Lore:Aedra_and_Daedra for example is never taken as gospel truth but might be a useful starting point.

Yes it was:

"What are dragons and why are they especially favored with immortality. Why no immortal bears? And the Gods knew that they had to depart the Mundus to let itcool. It is the rumbling of the Greybeards that wake him."

Also, from Nu-Mantia Intercept:

"The powers also created Red Tower and the First Stone. This allowed the Mundus to exist without the full presence of the divine. In this way, the powers of Ada-mantia granted the Mundus a special kind of divinity, which is called NIRN, the consequence of variable fate.

After these two acts, which is commonly called the Convention, the gods left the earth."

So there is definitely precedent.

Furthermore, the Aedric Plane(t)s are clearly not on Nirn.

Though, I might still take issue with the idea that the Aedra were "aloof" to Nirn. It just doesn't seem like the best word to describe them. But Umpteen up there has a pretty good justification of the word.

It also appears in http://www.uesp.net/wiki/Lore:Before_the_Ages_of_Man: Magnus leaves, and the gods convene at Adamantine to determine their course of action. "Most left when Magic did. Others sacrificed themselves into other forms so that they might Stay (the Ehlnofey). ... With Magic (in the Mythic Sense) gone, the Cosmos stabilized." Interestingly, the gods in general weren't important here; it was Magnus whose departure was most important for the stabilization of Mundus.